Zenith Carbs Question

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Alan Winer
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Zenith Carbs Question

#1 Post by Alan Winer »

I have rebuilt both Zenith Carbs, totally disassembled, cleaned, flattened surfaces, etc, etc,. Floats levels have been set correctly, checked and rechecked and rechecked, float is good no leaks, accelerator pump is set.
The question: On one carb only, I am getting gas weeping out of the idle air jets and the air correction jets on top. A very small amount, it's almost like condensation. The fuel level isn't that high, so I'm perplexed.
Any information would be appreciated.
Thanks,
Alan

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John Brooks
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Re: Zenith Carbs Question

#2 Post by John Brooks »

Look at the inside of the top of the carb, see I'd there is something in the vents, from the sides to the center vent hole. Sounds like tempertature and pressure changes and pushing gas on the air side.
John Brooks

62 Roadster
66 912
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getting pushed around in porsches since 1965

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Alan Winer
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Re: Zenith Carbs Question

#3 Post by Alan Winer »

The vents are clear. I am still getting weeping gas from where the mixture tube holders insert into the carb body-see first photo. As seen in the second photo the floats are set at 18.5mm (B) and this is just below where the holder inserts into the body (A) and they are not a sealed fit. So is it possible that this is just gas weeping up? I have checked the float valve, float and the level holds at 18.5mm under pressure. Only happening on one carb.
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Mike Ruddy
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Re: Zenith Carbs Question

#4 Post by Mike Ruddy »

Hello Alan, my Zeniths wept too. Here's a thread about leaky Zeniths which covers just about every eventuality.

viewtopic.php?f=1&t=41929

I make my appearance in act three (page 6) and am leak free by the time the curtain falls. Loctite is the secret of my success.

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Alan Winer
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Re: Zenith Carbs Question

#5 Post by Alan Winer »

Thanks Mike,
I don't know how I missed that thread in my search. It does cover all.....
The mysteries of Zenith Carb leakage are debunked in Ron LaDow's great article, "Leak no more", in the Registry Vol. 49 no.6
Alan

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